Collection of white blood cell-reduced plasma by apheresis

WBC reduction of cellular blood components has been introduced in many countries. Owing to concerns of residual WBCs in plasma, a new method to collect WBC-reduced plasma by apheresis was studied.

An apheresis machine (PCS2, Haemonetics) was used, in combination with the "high-separation" core (HSC) bowl, a redesigned version of the blow-molded (BM) bowl. With the BM bowl collections as control group, various software settings were investigated applying the HSC bowl. The optimized program was validated for routine application. Results are expressed as means +/- SD.

Plasma collected in the control group with the BM bowl (n = 25) had a volume of 622 +/- 7 mL and contained 5.3 +/- 4.6 x 10(6) WBCs per L, 11 +/- 5 x 10(9) PLTs per L, and 0.063 +/- 0.051 x 10(9) RBCs per L. The collection efficiency was 17.8 +/- 2.8 mL per minute, and the total procedure time was 36.1 +/- 6.3 minutes. The HSC bowl produced plasma that had a volume of 623 +/- 9 mL and contained 0.01 +/- 0.02 x 10(6) WBCs per L, 2 +/- 2 x 10(9) PLTs per L, and 0.00040 +/- 0.0016 x 10(9) RBCs per L (n = 134, all p < 0.001). The collection efficiency was 15.8 +/- 2.2 mL per minute, and the collection time was 40.3 +/- 6.3 minutes (both p < 0.001).

The HSC bowl with the new software reliably produces WBC-reduced apheresis plasma, with a slight elongation of the procedure time.